What should I do to set up the constraint on UICollectionView - ios

I have a tableview which shows the news. And there's a UICollectionview inside each UITableview cell. Also there'll be some images inside collection view cell and the number of cells cannot be fixed because news may contain one image, two images or more.
The
UITableview cell looks like the following structure :
xxxxxxxxxxxxxxxxxx
name
news info
(UICollectionview img1 img2...)
UIButton and UILabel (such as like, dislike, comment..)
xxxxxxxxxxxxxxxxx
and I also set up the constraints. And I have to set up the width attribute for the UICollectionview. The main issue is that no matter how many images I may have for the news, the collection view will be always that wide and will block the click event for the tableview cell. So any ideas for that,
thx!

here is a suggest:
set the initial width constraint to 0, then changing it to actual width when bind data to cell.

Related

UITableView + UICollectionView + UITableView sizing issue

Below attached image is representing my requirement:
In this image the yellow color UITableView will have list of different UITableViewCell items. In one of the UITableViewCell it has UICollectionView with its list of UICollectionViewCell items and the scroll direction for the UICollectionView is set to horizontal
Each UICollectionViewCell will have one UITableView (Highlighted in Red Color) and it will have its list of UITableViewCell (Highlited in Rose Color) items. Here, the UITableViewCell (Highlited in Rose Color) item can collapse/expand. Whenever the cell is collapse/expand the red table's content size is handled automatically. But, whenever the red table's content size is increased the collectionview size is not increasing.
I have added all relevant constraints to these UI elements. But, the content size or frame of the collectionview is not expanding when a tableview cell is expanded.
To understand better here i am breaking it down how the views are designed:
Yellow tableview embedded inside a UIViewController and it will have one simple UITableViewCell which has no custom class
To the cell programatically the UICollectionView will be added. This UICollectionView is placed in one xib file and it has embeded inside a UIView
UICollectionViewCell has been created in one xib and it will have UITableView element inside.
Also, UITableViewCell has its own xib to refer and this is the cell which will gets expand/collapse
I have tried modifying the intrinsicContentSize property to modify the UICollectionView property's height where it has embedded inside UIView element whenever the expand is happening. Please, refer the CardView.swift for the reference.
CardView.swift
I know the design is bit complex. But, what am i missing here?
Based on your requirement in the image, I just created a sample project here.
I did not use separate Xibs. However, I was able to achieve what you asked for.
You might have to handle the reload of the innermost tableView better based on your apps business logic.
Here's what I have implemented:
The top most view controller has a parent table view.
This table view cell consists of a child collection view.
The child collection view cell consists of a grand child table view.
The grand child table view is the one corresponding to the table view Highlited in Rose Color in the question.
To answer your question about the collection view not expanding: to expand the child collection view when the grandchild table view cell is tapped, I am reloading the parent table view by increasing the row height for the cell containing the collection view. Hence you don't have to worry about adjusting the constraints in auto layout
In case you want to add additional content into the child collection view cell, you can add a height constraint to the grand child table view with a low priority and modify that whenever you need to expand the content in the grand child table view.
if you want to achieve point 6, as suggested by #Ramy Al Zuhouri, you might have to call: collectionView.performBatchUpdates before collectionView.reloadData() to expand the cell size
Refer to the video below for better understanding
This doesn't necessarily solve your problem, but sometimes it's a matter of forcing the collection view to invalidate its layout and recalculating its size. I once received an answer to a TSI from an Apple enginner:
So this is old fashioned way of forcing a re-usable container (Collection || Table) to invalidate its layout. You may even be able to just call invalidate layout. There are oddities in the system with AutoLayout and animations that sometimes throw the system into an odd state. If we do the above the container and can invalidate its layout and make updates without need to re-calculate + incorporate animations. To summarize, calling performBatchUpdates with nil parameters can be useful if you need to force an update based on layout content (not necessarily datasource changes).
It looks like a hack to be used with caution, but it can be worth to give it a try. Whenever you need to recalculate the size of the collection view's cell to expand or shrink, you can do this:
UIView.setAnimationsEnabled(false)
collectionView.performBatchUpdates(nil, completion: nil)
UIView.setAnimationsEnabled(true)
collectionView.reloadData()
This forces a reload, and UIKit is able to recalculate the height of the cell given that you update the height. How? In my case I did by updating a height constraint, but there are multiple ways of doing this. However, it's intended that as the reload happens the collection view should be aware of the new cell height.
the good approach for this, you have to add collectionView in the tableViewHeader
then whenever you scroll up your tableView your collectionView section will also scroll up
to load cells on the specific indexes follow bellow steps:
if(indexpath.row == 0){
//load first tableView cell with collection view
}
else if (indexpath.row == 1){
//load second tableView cell with collection view
}
else{
//load table view cell here
}

UITableView inside UITableViewCell height not working as expected

I have a UITableView which have some cells that will be always be there, one cell with a UICollectionView in it that will act like tabs, and finally one cell with a UITableView in it, whose data will change.
Then when the user selects one of this "tabs", I want to reload the nested table to show the correct data rows (the height of this rows will be dynamic).
I have already achieved that the nested table changes on the collection item selection, but the problem I am facing is that the UITableView inside the cell is not sizing properly.
I have build a sample app just to simplify the views. As you can see in the screenshot, the cell that contains the table is not filling the rest of the screen, so the 10 rows are not visible unless you scroll this table.
What I want is this table to fill the rest of the screen. The user must be able to scroll the main tableview, not the nested one, and still see all of the nested table cells.
I can't do this with multiple sections because I will have a header section that will be always fixed on top, if I had another section, it's header will replace the sticky one on scroll.
I have set the rowHeight of the main UITableView to UITableViewAutomaticDimension and an estimatedRowHeight too. I have pinned it to top, left, right and bottom of the cell's ContentView.
Can you help me with this, please? If it helps, I could upload the sample project and link it here.
Thank you very much!
If you are using autolayout then,
Give height constant to nested table view, create outlet for that height constraint.
When you reload that nested table, you will get that table's content size.
Fetch height from that content size and modify height constraint.

How to make a particular static cell in UItableview self adjusting according to the constraints of the contents inside it

I've done some research on self adjusting static cells but they seem to apply to the entire table view as a whole.
what if I'm only interested in targeting a specific cell like the picture below? How do I go about doing it?
edit: What I intend is for the tableview cell to expand when the collectionview gets populated with more cells. Thus allowing the entire page to scroll accordingly.
Are the images in the collection view always the same height ? If the images in the view are a static size, you could just divide the number of images, by the number that will fit on a line. Then multiply that by the height of the lines to set the tableview cell height.
This might be helpful:
Dynamic Sized Tableview Cells

UICollectionView within UITableView. How to tell tableview cell to change height when collection view gets taller?

I have a UITableView and one of my table cells is a UICollectionViewController subclass that contains a UICollectionView of displayed email addresses. When a user adds an email the UICollectionView and it’s cell in the table view should get taller.
I’m currently attempting to do this setting my collectionView height constraint to collectionView.contentSize.height in the LayoutSubviews method of my collection controller/cell class. My issue is that the cell in the UITableView is not changing size when this happens.
I am assuming that this is because there is nothing telling the table view that the height of the email entry cell has changed. I am currently using dynamic cell sizing - or trying to anyway. Even, if I call tableView.reloadData() this still does not work. I’m wondering if someone could give me a high-level idea of how they would set this up.
UPDATE:
I had a broken constraint issue that was part of my problem, but this is still not solved. While have proven that I can update the height constraint and that will update the size of the collection view, it's out of sync. It's always one update behind. Here's an image showing the 'UICollectionView' in green and you can see in the logs that I'm updating the constraint (yes, multiple times) each time after adding a new item to the collection, but it is not updating the bounds of the view instance. In this example, if I were to add a new item to the collection, the next time I inspect bounds.height it would be at 149.5. What am I missing!?
i had answered this question in another tableview inside tableview cell that will work for collection view too ,i explained it in this thread
ask me if you faced any problem
It seems you want to set the height of your table view cell dynamically. This detailed tutorial walks you through making a custom cell class that will have dynamic height. Unfortunately, this tutorial only walks you through how to do this with auto layout constraints and a storyboard. In the tutorial you'll notice that the height of the cell depends on the constraints put on a title label within the cell. Try doing the same thing, but applying the constraints on the content in your cell (the collection view cell).
http://www.raywenderlich.com/73602/dynamic-table-view-cell-height-auto-layout

How to set the height of prototype cells in an iOS table views

I have a table view with a prototype cell containing both disclosure and detail accessories. I want to use a font size of 12 in the cell and reduce the row height accordingly. Thus the size of the two accessory icons need to be reduced in size as well. I assumed this would be one of the more obvious things one might want to do with a table view but fail miserably in figuring out how?
Assuming you are have a nib or storyboard, you should see a resize handle on the cells when you select a cell in the editor. Just grab and resize.

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